delphi怎样把子窗体显示在pagecontrol的tabsheet

https://bbs.csdn.net/topics/391980918

unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.ComCtrls, Vcl.StdCtrls,
  Unit2;
type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    PageControl1: TPageControl;
    TabSheet1: TTabSheet;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  Form2: TForm2;
implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  if not Assigned(Form2) then
    Form2 := TForm2.Create(nil);
  try
    Form2.ManualDock(PageControl1.Pages[0]);  // 嵌入PageControl1.Pages[0]
    Form2.Show;
  except
    Form2.Close;
    Exception.Create('Error');
  end;
end;

end.